A disk brake apparatus mounted on a vehicle is generally so arranged that brake pads opposed to two faces of a disk rotor are pushed against the two faces of the disk rotor by a caliper piston fitted in a caliper cylinder. This disk brake apparatus varies its braking force according to a brake fluid pressure supplied to the caliper cylinder.
Proposed as the disk brake apparatus of this type is one so arranged that the push position of the brake pads by the caliper piston is set at a radially outside location of the disk rotor to improve braking performance (e.g., cf. Japanese Patent Application Laid-open No. 9-280280).